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Removing rusted or broken bolts and screws

Speaking of anything from an 8/32 screw to a 3/4" bolt. How do you do it? I'm on a job where we had a heck of a time getting a 3/8" bolt out of a tapped flange. My usual procedure is to heat the bolt up red hot and tap on it with a hammer while heating it, let it cool down, and soak it with a penetrant like CRC Screwloose. When it cools down, I get on it with some vise-grips, and it usually comes out without much effort.

On this bolt, we drilled the center and tried two different kinds of screw extractors. Broke off both of them inside the bolt. Had to use a dremel tool with a tungsten carbide bit to grind out the screw extractors, then drill and re-tap the hole. What a pain in the azz!

Another one we had trouble with was a little 8/32 screw holding a small terminal plate. The screw broke off, and I went to drill it out with a cobalt bit. I broke the bit in the hole. Had to drill that bit out with another one and re-tap the hole.

Anyways, I was just curious what sort of tactics the rest of you are emplying when you encounter a rusted/seized/broken bolt. I bought a set of Lisle screw/bolt/stud extractors today, and I was also wondering if anyone here has ever used them with any success???

Soak for 15 minutes with a penetrating oil. If it's a larger bolt I go for the impact. Hammer on it and either it comes out or it snaps. If it's a phillips or flat, I'll try it but shortly there after I'm looking for something to cut it off with. Patience, patience, patience! If its broke in a 4x4 box in a refrigerator I just rip it all out and start over.

I've used the craftsman extractors on lots of things with great success when dealing with stripped bolts. These things were lifesavers on my old Mustang restoration.
As far as the drill and screw in type extractors, Snap On were the only ones that could really hold up for me without breaking, especially the smaller ones.

Same tactics. Pen lube and heat normally gets it done. I have welded nuts onto broken studs. The intense heat and new gripping surface really help. Have used the bolt outs like the ones shown from craftsman and have had good luck with them. Never had much success with the screw in type extractors. It would always just seem to make me more pissed when the not so ez out would break.

I've used the craftsman extractors on lots of things with great success when dealing with stripped bolts. These things were lifesavers on my old Mustang restoration.
As far as the drill and screw in type extractors, Snap On were the only ones that could really hold up for me without breaking, especially the smaller ones.

I looked at that exact same kit when I was in Sears today. I'll pick it up next week. I don't like the "not-so ez out" drill and screw in type extractors either. The only time they have worked for me is when I use them on broken 1/4" NPT and 1/2" NPT pipe nipples. Every time I have used one on a broken bolt, it has broken before before the bolt did. I think I am officially done with those things.

Originally Posted by caheiman30

I've used transmission fluid mixed with nail polish remover and it works good

Sounds interesting... Although I gotta admit that the idea excites my b.s. detector just a little. What is the mixture ratio? What about it makes it work better than other penetrating lubricants?

Originally Posted by Joehvac25

Heat the bolt but don't let it cool, every time I have that problem I get it red hot and get on it right away and as it cools it gets harder and harder to turn.

Yup, that works too. If you can get them moving while they're hot, then you're better off that way. Bolts do expand as they heat up and sometimes that can make them harder to turn when they're hot. The heat and expansion is what breaks the chemical bond with the material that surrounds it.

Not breaking bolts is something that requires a certain touch and feel that only comes with experience. Experience only comes after you need it. I've found if you tighten the bolts a little before you try to loosen it, most of them come out easily. Sometimes you have to just go back and forth with it before it comes all the way out.